JPH05333587A - Electrostatic latent image developing toner - Google Patents

Abstract

PURPOSE:To obtain a toner having a small particle size having a narrow distribution of particle size with improved electrification property and cleaning property by fixing charge resin fine particles to the toner surface. CONSTITUTION:After color fine particles comprising at least a resin and a coloring agent are granulated in a wet state, the coloring fine particles are mixed in a wet state with charge resin fine particles having 1/10-1/200 average particle size of the coloring particles in wet dispersion. Then, the electrifying resin fine particles are deposited on interfaces of the coloring fine particles, molten and fixed to form blocks and pulverized. As for the electrifying fine particles, negative resin fine particles or positive resin particles are used according to the electrification property of the toner. As for the negative resin fine particles, fluorine-contg. resin, styrene resin, etc., is used, and as for the positive resin particles, resin fine particles consisting of amino groups and/or nitro groups-contg. monomers are used.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a toner for developing an electrostatic latent image. More specifically, the present invention relates to a toner for developing an electrostatic latent image, which is produced by subjecting toner particles to wet granulation, aggregating and crushing steps.

[0002]

2. Description of the Related Art In recent years, high image quality is required in the field of electrophotographic copying machines, printers, and the like. In order to meet this demand, a reduction in toner particle size is being actively studied. Conventionally, a pulverization method has been often used as a method for producing toner. The pulverization method is performed by melt-kneading a binder resin colorant and the like, and pulverizing and kneading the kneaded product.

However, the toner obtained by this pulverization method is
The particle size distribution of the toner particles is wide, and there is a limit in terms of reducing the particle size of the toner from the technical point of view and productivity.
Wet granulation methods such as suspension polymerization method and suspension granulation method can be applied to smaller particle sizes and are more advantageous in terms of productivity than the pulverization method. This method uses a polymerizable monomer, a colorant,
Other methods include adding other additives, synthesizing the toner in a suspended state, and granulating.

The toner obtained by such a wet granulation method is a spherical particle having a small particle size and a narrow particle size distribution, but since the shape is close to a spherical shape, there is a problem that the cleaning property is poor due to a blade or the like. .. Further, there is a difficulty in controlling the triboelectricity. The reason for this is not clear, but it is considered that the surface area effective for triboelectric charging is small due to the spherical shape, and that impurities such as surfactants and polymerization catalysts during polymerization / granulation remain as contamination. ..

Various proposals have been made to solve the above problems (for example, Japanese Patent Laid-Open No. 2-273757). This publication discloses adding inorganic fine particles or organic fine particles at the time of thermal aggregation in a method of producing a toner in which thermal aggregation is performed after suspension polymerization and the thermal aggregation is crushed.

The fine particles to be added are intended to improve the crushability as a subsequent step and stabilize the charging property. A charge control agent (CCA) is used to control the charge of the toner. Conventionally used CCA has a large particle size (for example, several μm) and has a high cohesive property, so that it is difficult to form a uniform charged surface, and it is particularly difficult to apply it to the wet granulation method.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a toner having a narrow particle size distribution and a small particle size, and having an improved electrostatic cleaning property. To do.

[0008]

That is, the present invention relates to a toner produced by granulating particles comprising at least a resin and a colorant in a wet process, and then performing an aggregating, drying and crushing process. The present invention relates to a toner having charged resin fine particles fixed on its surface.

In the method for producing the toner of the present invention, particles comprising at least a resin and a colorant are granulated in a wet process. As a method for granulating toner particles in a wet state, any of known wet granulating methods may be used, and may include a polymerization process such as a suspension polymerization method or an emulsion polymerization method, or a suspension method. It may be a granulation method by melt dispersion such as. In the case of the suspension polymerization method, a polymerization composition containing a polymerizable monomer capable of forming a resin component as a binder as described below, a polymerization initiator, and a colorant and other additives is used as a non-solvent medium. Granulation is carried out by suspending and polymerizing.

In the case of the emulsion polymerization method, it is preferable to use the method known as the seed polymerization method because the particle size distribution is good but only extremely fine particles can be obtained by the general emulsion polymerization. .. That is, a part of the polymerizable monomer and a polymerization initiator are added to an aqueous medium obtained by adding an aqueous medium or an emulsifier to emulsify the mixture with stirring, and then the rest of the polymerizable monomer is gradually dropped to obtain fine particles,
The particles are used as seeds to carry out polymerization in droplets of a polymerizable monomer containing a colorant and other additives.

In addition, as a wet granulation method including a polymerization process, a soap-free emulsion polymerization method, a microcapsule method (interfacial polymerization method, in-situ polymerization method, etc.), a non-aqueous dispersion polymerization method and the like are known. .. In the case of the suspension method, a resin component as a binder, which will be described later, is mixed with a colorant and other additives, melted, and suspended in a non-solvent medium for granulation.

The average particle size of the toner particles thus granulated in the wet process is preferably 1 to 15 μm, particularly 2 to 10 μm. In the production method of the present invention, the average particle size is as described above in the liquid medium. After granulating the toner particles (referred to as “toner base material”), the chargeable resin fine particles (hereinafter abbreviated as fine particles) described below are added to the obtained toner particles and stirred.

As such fine particles, (-) chargeable resin fine particles or (+) chargeable resin particles can be used depending on the chargeability of the toner. (-) Chargeable resin fine particles include fluorine-containing resin, for example, tetrafluoroethylene (PTFE) resin, trifluoroethylene resin, perfluoroalkoxy (PFA) resin, perfluoroethylene propylene (FEP) resin, fluorine ethylene propylene ether. (EPE) resin, ethylene-tetrafluoroethylene (ETFE) resin, vinylidene fluoride (PVDF) resin, vinyl fluoride (PVF)
Resin, chlorotrifluoroethylene (CTFE) resin, ethylene-chlorotrifluoroethylene (ECTFE) resin, trifluoropropylene resin, hexafluoropropene, hexafluoropropylene, vinylidene fluoride, etc. and 2,2,2-trifluoroethyl acrylate ,
2,2,3,3-tetrafluoropropyl acrylate,
Fluorine-containing various fluoroalkyl acrylates such as 2,2,3,3,4,4,5,5-octafluoroamyl acrylate, 1H, 1H, 2H, 2H-heptadecafluorodecyl acrylate and / or fluoroalkyl methacrylates Polymers containing at least monomers (including copolymers of styrene, (meth) acrylic, methacrylic acid, acrylic acid, etc.) can be used.

Further, styrene resin and styrene /
A (meth) acrylic copolymer resin having a styrene-rich composition, a composition having methacrylic acid or acrylic acid added, and a polymer having a sulfonic group-containing monomer can also be preferably used.

Other polyester-based resins, silicone-based resins, polyethylene-based resins, etc., as well as resin particles obtained by treating various resin particles with a coupling agent containing a fluorine group, for example, which has a function of enhancing negative chargeability, and various negatively charged particles. Resin fine particles obtained by treating the surface with a control agent such as a chromium complex salt type dye can be used. As the surface treatment with a chromium complex salt type dye, for example, a charge control agent such as alcohol (water / alcohol)
By selecting a solvent such that (CCA) dissolves but not resin fine particles, CCA is dissolved in the solvent and the resin fine particles are mixed therein, whereby the surface of the resin fine particles can be treated with CCA. By doing so, the chargeability of the resin fine particles can be improved. This can be achieved by coating the surface of the resin fine particles by spraying with a solution in which CCA is dissolved when the resin fine particle dispersion liquid is dried. For this method, a device such as Dispercoat (manufactured by Nisshin Engineering Co., Ltd.) is preferably used. Fine resin particles are dispersed in an air stream, and C is dispersed in the dispersed air stream.
By spraying the solution in which CA is dissolved from the nozzle, the surface of the resin fine particles can be treated with CCA.

For this method, for example, an apparatus such as Coatmizer (manufactured by Freund Industrial Co., Ltd.) or Disper Coat (manufactured by Nisshin Engineering Co., Ltd.) can be preferably used. Although the range of use of the solvent is limited in the above method, the method has a high degree of freedom. On the contrary, this dispersion liquid can be directly used for the wet addition of the present invention by the wet treatment, but since the method is powdered, it is necessary to use it as a powder or to redisperse it in the wet treatment. As the (+) chargeable resin particles, resin fine particles made of an amino group- and / or nitro group-containing monomer can be used. The amino group-containing monomer has the following general formula [I]

[0017]

[Chemical 1] (Wherein R ₁ is hydrogen or a methyl group, R ₂ and R ₃ are hydrogen or an alkyl group having 1 to 20 carbon atoms, X is an oxygen atom or a nitrogen atom, and Q is an alkylene group or an arylene group). There are amino (meth) acrylic monomers that are used.

Specific examples of the amino (meth) acrylic monomer include, for example, N,
N-dimethylaminomethyl (meth) acrylate, N, N
-Diethylaminomethyl (meth) acrylate, N, N-
Dimethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, p-N, N-
Dimethylaminophenyl (meth) acrylate, p-N-
Laurylaminophenyl (meth) acrylate, p-N-
Stearylaminophenyl (meth) acrylate, p-N,
N-dimethylaminobenzyl (meth) acrylate, N,
N-dimethylaminoethyl (meth) acrylamide, N,
N-dimethylaminopropyl (meth) acrylamide etc. are mentioned. Other amino group-containing monomers include N,
N-dimethylaminostyrene, N-methylol methacrylamide, methacrylamide and the like can also be used.

The nitro group-containing monomer has a nitro group in the monomer and is not particularly limited as long as radical polymerization is possible, and examples thereof include nitrostyrene.
Further, a (meth) acrylic resin and a styrene / (meth) acrylic copolymer resin having a (meth) acrylic rich composition can also be preferably used. Other amide resin,
Urethane resin, epoxy resin, benzoguanamine resin,
Further, melamine resin or the like, resin particles obtained by treating various resin particles with a coupling agent having an action of enhancing positive chargeability, for example, an amino group-containing coupling agent, and various positive charge control agents such as nigrosine dye on the surface Can be used (the processing method is the same as that of the negative charge control agent).

In addition, various types of chargeable resin fine particles are produced by a wet granulation method in order to improve charge stability, particularly charge stability under high temperature and high humidity, and the amount of the surfactant is suppressed as much as possible. For example, it is preferably used after being produced by a soap-free emulsion polymerization method or the like, or after being granulated, sufficiently washed with water / alcohol or the like, or after the surface is subjected to a hydrophobic treatment with a coupling agent or the like.

It is desired that the size of the fine particles used is 1/10 or less of the average particle size of the granulated toner particles, and more preferably about 1/200 to 1/10. That is, if the size of such fine particles is larger than 1/10 of the average particle size of the toner particles, they are easily desorbed during crushing. If it is less than 1/200, the particles are entrapped in the toner particles and the crushability and chargeability cannot be improved.

The amount of such fine particles added is 0.1 to 30 parts by weight, preferably 1.0 to 30 parts by weight, and more preferably 1.0 to 15 parts by weight, based on 100 parts by weight of the toner particles. That is, if the amount of such fine particles added is less than 0.1 part by weight, the amount of the fine particles adhering to the surface of the toner particles may be insufficient, and these particles may not function effectively. If it exceeds the range, fine particles that cannot adhere to the toner particle surface with sufficient strength are generated, and these particles may separate from the toner particle surface during use and adhere to the developing sleeve, resulting in toner spillage. This is because.

As a method for adding the fine particles, (a) a mode in which the base material and the chargeable resin particles are mixed in a wet method and then agglomerated (b) a chargeable resin particle after the base material is agglomerated in the wet method And (c) the base material is coagulated and dried to form a block, and then the chargeable resin fine particles are added and mixed, followed by crushing.

In the method (a), a wet-granulated toner base material particle dispersion liquid (suspension) (hereinafter referred to as liquid (A)) and a wet-granulated resin fine particle dispersion liquid (hereinafter referred to as ( (Solution B)) is prepared, solution (B) is added to solution (A), and then mixed and stirred. At this time, it is desirable that the chargeable resin fine particles are attached to the surface of the toner base material as uniformly as possible. Also, (A)
Liquid (B) may be mixed at once with liquid (B) in liquid (A).
The solution may be added sequentially (or vice versa). In any case, it is important that the chargeable resin fine particles are present at the interface between the toner base material and the base material during aggregation in the next step.

In the liquid (B), the particles obtained by wet granulation as described above are once made into a cake shape, dried and then dispersed again in a solvent that does not dissolve the resin such as water or alcohol. Or a liquid obtained by treating particles obtained by a gas phase method or the like by the same method.

In the method (b), the chargeable resin fine particles are treated in a wet process in the same manner as the method (b). However, in the method (b), the chargeable resin particles are added after the base material is aggregated, and therefore the chargeable resin particles do not exist at the interface between the base material and the base material. In this method, the final toner surface is treated while the block-like material formed by agglomeration in the step of crushing after drying and the chargeable resin fine particles are dispersed. The other processing methods and the like are the same as the method (a).

In the method (c), the handling property is excellent because the powders are treated with each other, but the chargeable resin fine particles are not present at the interface between the base material and the base material as in the method (b). As for the improvement of crushability (sharp particle size distribution, small amount of fine powder), it cannot be expected as much as the method (a). It is sufficiently effective in imparting chargeability to the toner.

In the methods (b) and (c) above, the various organic / inorganic fine particles present at the interface between the base material and the base material at the time of agglomeration are treated to improve the disintegration property. It is preferable to impart the electric charge by using the chargeable resin fine particles disclosed in 1. In addition, the above (a), (b) and
You may combine and process all three methods of (C). In addition, various conventional particles other than the chargeable resin particles, for example, various organic / inorganic particles may be used in combination in each of the above methods.

As another method, it is possible to adopt a mode in which the wet granulation product is dried and then the fine particles are added (powder-powder mixture). As a method of aggregating the toner particles, several modes are conceivable, and when the fine particles are added to the toner particles in a wet process, for example, prior to the drying step, the liquid medium in which the toner particles are dispersed is subjected to heat treatment (for example, A temperature higher than the glass transition temperature (Tg) of the resin contained in the toner particles and lower than the boiling point of the liquid medium), and containing a non-aqueous solvent having solubility or swelling property with respect to the resin prior to the drying step. Contacting the solution with the toner particles, or setting the temperature and / or pressure in the drying step to a certain degree higher than general drying conditions,
Alternatively, there is a method in which a solution containing a non-aqueous solvent that is soluble or swellable with the resin component contained in the toner particles is brought into contact with the toner particles in the drying step. Of course, it is possible to combine some of the above processing methods. Further, in the method of
By storing under a high humidity condition after the drying step, more appropriate cohesiveness can be obtained. Further, the toner particles are heat-treated in a dry method (the glass transition temperature (Tg) of the resin contained in the toner particles or higher and the softening temperature (Tm) + 60 ° C.
The following temperature may be used, or the toner particles are brought into contact with a solution containing a non-aqueous solvent which is soluble or swellable in the resin component contained in the toner particles, and then dried again. Of course, also in this case, it is possible to combine both processing methods.

By carrying out such a treatment, the surface portions of the toner particles are melted, dissolved or swollen, and the toner particles are bonded to each other to cause aggregation. The cohesive force between the toner particles in this aggregation depends to some extent on the particle size of the particles. The smaller the particle size, the greater the bonding strength. Therefore, the bonding force of the particles included in the main particle size range (for example, a particle size of about 2 to 8 μm) of the toner particles formed in the wet granulation in mutual bonding is relatively weak, and the particles are almost bonded by a small external force. Even in the state of agglomeration that can be crushed from the site, the binding force to the larger particles within the above-mentioned particle size range of ultrafine powder having a diameter of 1 μm or less, for example, is sufficiently large. Even if the above-mentioned external force is applied to these ultrafine powders, there is little possibility that they will be dissociated again.

In the manufacturing method of the present invention, the drying treatment of the toner particles is performed after the aggregating treatment as described above, at the same time as the aggregating treatment or before the aggregating treatment. It may be carried out by using a general drying device as conventionally used, but in the case where the drying process is carried out at the same time as the aggregating process, that is, when the toner particles are agglomerated in the drying step, the medium fluidized drying device is used. (For example, MSD manufactured by Nara Machinery Co., Ltd.), wet surface modification device (for example, Dispercoat manufactured by Nisshin Engineering Co., Ltd.), and the like can be preferably used. Further, after the aggregating step and the drying step as described above, the obtained dried toner particle agglomerates are subjected to a crushing step.

Since the crushing step in the conventional crushing method obtains particles having a small particle size from a completely lump, it consumes an extremely large amount of energy, and in terms of equipment, cost and running cost. Occupies a large weight, but the crushing step in the production method of the present invention is a simple one because it crushes aggregates that were originally in the form of particles.

In the present invention, as an apparatus used for crushing such toner aggregates, various crushers used in the conventional crushing method can be used. Among them, the rotor is especially used. A mechanical crusher for crushing particles is preferably used in the process of passing through a shortest gap of 0.5 to 10 mm formed by a rotor and a rotor or a stator and a rotor in a state of being dispersed in an air current moving at high speed. For example, Kryptron System Cosmos (made by Kawasaki Heavy Industries Ltd.)
Fine mills (manufactured by Nippon Numacku Kogyo Co., Ltd.), turbo mills (manufactured by Turbo Kogyo Co., Ltd.), cosmomizers (manufactured by Nara Machinery Co., Ltd.) and the like can be mentioned as desirable devices. Furthermore, by using a surface modification device such as a hybridization system (manufactured by Nara Machinery Co., Ltd.) that uses the high-speed air impact method, at the same time that the toner aggregates are disintegrated, the particles added to the toner particle surface are added. It is desirable that the fine particles and their ultrafine powder can be more firmly fixed by mechanical impact force.

In the toner particles obtained by crushing in this way, fine particles are firmly bonded to the surface of the toner particles, and the proportion of ultrafine particles contained in the toner particles is small, and the particle shape thereof is also small. Since it has undergone the process of agglomeration and disintegration, it has changed from a wet granulated sphere to an irregular one. The shape of the toner particles finally obtained can be manipulated to some extent from an irregular shape that is considerably close to a spherical shape to a shape that is not, depending on the degree of bonding at the time of aggregation.

Further, the toner particles obtained by crushing as described above are subjected to a classification step, if necessary, and subjected to air classification. The toner finally obtained by such a production method has an average particle size of 1 to 15 μm, preferably 2 to
The distribution is such that particles having a particle size of 10 μm and an average particle diameter of ± 25% are included in an amount of 50% or more, more preferably 60% or more. The toner for developing an electrostatic latent image of the present invention contains at least a resin as a binder and a colorant in the composition of toner particles, and the chargeable resin fine particles have toner agglomerated and crushed on the surface thereof. It is not particularly limited as long as it is bonded through the steps, and various constitutions such as magnetic or non-magnetic and charging polarity can be adopted depending on the developing method.

The resin contained in the toner is not particularly limited as long as it is generally used as a binder in a toner, and examples thereof include a styrene resin, a (meth) acrylic resin and an olefin. -Based resins, polyester-based resins, amide-based resins, carbonate resins, polyethers, thermoplastic resins such as polysulfone, thermosetting resins such as epoxy resins, urea resins, urethane resins, and copolymers thereof And polymer blends are used. The binder resin used in the present invention includes not only those in a complete polymer state such as a thermoplastic resin but also those in an oligomer or prepolymer state such as a thermosetting resin. In addition, a polymer partially containing a prepolymer, a crosslinking agent, and the like are also included.

Recently, there has been a demand for a technique capable of copying at a higher speed, and in the toner used in such a high speed system, the fixing property of the toner onto a transfer paper or the like in a short time and the fixing roller can be improved. It is necessary to improve the separability of. Therefore, in order to obtain a toner used in such a high-speed system, a homopolymer or a copolymer synthesized from a styrene monomer, a (meth) acrylic monomer, and a (meth) acrylate monomer as a binder resin. , Or it is desirable to use polyester resin, and its molecular weight is number average molecular weight (Mn).
And the relationship between the weight average molecular weight (Mw) and the Z average molecular weight (Mz) is 1,000 ≦ 7,000, 40 ≦ Mw / Mn ≦ 70,
200 ≦ Mz / Mn ≦ 500 and number average molecular weight (Mn)
Further, it is desirable to use a material satisfying 2,000≤Mn≤7,000. When used as an oilless fixing toner, it has a glass transition temperature of 55 to 80.
℃, softening point 80 ~ 150 ℃, 5-20% by weight
It is desirable that the gelling component (1) is contained. Also,
In order to improve the resistance to vinyl chloride, it is desirable to use a polyester resin, and a resin containing a gelling component in an amount of 5 to 20% by weight is particularly desirable.

When it is desired to obtain a translucent color toner used for OHP or full color,
As the binder resin, it is desirable to use a polyester resin from the viewpoints of vinyl chloride resistance, translucency as a translucent color toner, and adhesiveness with an OHP sheet. Further, in this case, the glass transition temperature is 55 to 55. 70 ° C, softening point 80
~ 150 ℃, its number average molecular weight (Mn) is 1,
A linear polyester having a molecular weight distribution (Mw / Mn) of 4,000 to 15,000 and 4 or less is desirable. Further, as a binder resin for obtaining a translucent color toner, a linear polyester resin (A) and a diisocyanate (B) are used.
Linear urethane-modified polyester obtained by reacting
(C) is also preferably used. The linear urethane-modified polyester referred to here is composed of a dicarboxylic acid and a diol, has a number average molecular weight of 2,000 to 15,000, and has an oxidation of 5 or less. 0.3 to 0.95 mol of diisocyanate per
A linear urethane-modified polyester resin obtained by reacting (B) and having a glass transition temperature of 40 to 40.
The main component is one having an oxidation of 5 or less at 80 ° C. Furthermore, it is a polymer obtained by modifying a linear polyester with a styrene-based, acrylic-based, aminoacrylic-based monomer or the like by copolymerization by a method such as block polymerization or block polymerization, and has the same glass transition temperature, softening point, and molecular weight characteristics as above. A thing is also used suitably. The colorant contained in the toner obtained by the production method of the present invention is not particularly limited, and various known organic or inorganic pigments and dyes of various colors can be used.

Usually, with respect to 100 parts by weight of the binder resin,
It is desirable to use 1 to 20 parts by weight, more preferably 2 to 10 parts by weight. That is, if the amount is more than 20 parts by weight, the fixing property of the toner is deteriorated, and if the amount is less than 1 part by weight, a desired image density may not be obtained. When preparing a magnetic toner, a magnetic substance such as magnetite, γ-hematite, or various ferrites may be added.

An offset preventive agent may be used in order to improve the fixing property of the toner. Specifically, various waxes, particularly low molecular weight polypropylene, polyethylene, or
Polyolefin waxes such as oxidized polypropylene and polyethylene, and natural carnauba wax are preferably used.

To the toner of the present invention, a fluidizing agent for improving fluidity or a cleaning aid for improving cleaning ability may be added. As the fluidizing agent, various metal oxides such as silica, aluminum oxide, titanium oxide and magnesium fluoride are used alone or in combination. Examples of the cleaning aid include inorganic fine particles described above as fluidizing agents, metal soaps such as stearates, fluorine-based, silicon-based, styrene- (meth) acrylic-based, benzoguanamine, melamine, and various synthetic resin particles such as epoxy. Used. Hereinafter, the present invention will be described using examples.

Example 1 (Production Example A of Toner) Production Method of Core Particles 160 g of styrene, 90 g of butyl methacrylate, 3 g of isobutyl acrylate, 5 g of low molecular weight polypropylene (Viscor 605P; manufactured by Sanyo Chemical Industries), 2 g of lauryl mercaptan, silane. Coupling agent (TSL831
1; Toshiba Silicone Co., Ltd.) 2 g, carbon black (# 23
00; Mitsubishi Kasei Co., Ltd.) 10g, magnetic magnetite (EP
T-1000; manufactured by Toda Kogyo Co., Ltd.) (50 g) and azobisisobutyronitrile (6 g) were mixed with a sand stirrer to prepare a uniform dispersion liquid of the polymerization composition. Next, as a dispersion stabilizer, methylcellulose (Methocel K35LV; Dow Chemical Co., Ltd.) 4 wt% solution 60 g, dioctyl sulfosuccinate soda (Nikkor OTP-75; Nikko Chemical Co.) 1 wt% 5 g, sodium hexametaphosphate (Japanese) (Koujunyaku Kogyo Co., Ltd.) Using a homogenizer (manufactured by Tokushu Kika Kogyo Co., Ltd.) in an aqueous solution prepared by dissolving 0.3 g of 650 g of ion-exchanged water, the above homogenous dispersion liquid was homogenized to a particle size of 3 to 10 μm. The number of rotations was adjusted and the suspension was suspended in water. The suspension was transferred to a four-necked flask and purged with nitrogen.
Polymerization is carried out for 24 hours at a stirring speed of 100 rpm at a temperature of 100 ° C., glass transition temperature (Tg) 54 ° C., softening point (Tm) 82 ° C., number average molecular weight (Mn) 8000, weight average molecular weight / number average molecular weight (M
Core particles a of w / Mn) 24 were obtained. Method for producing fine particles

0.4 g of ammonium persulfate was dissolved in 800 g of ion-exchanged water, transferred to a four-necked flask and heated to 75 ° C. while substituting with nitrogen, and dissolved in 140 g of styrene, 60 g of methyl methacrylate and 8 g of methacrylic acid. Charge and polymerize at a stirring speed of 400 rpm for 6 hours,
Fine particles having an average particle size of 0.2 μm and a glass transition temperature of 80 ° C. were obtained. Method for producing toner particles: 2% of fine particles a are added to 800 g of 28% by weight slurry of core particles a.
170 g of 0 wt% slurry was added and dispersed in 1000 g of ion-exchanged water, and 5 g of ammonium persulfate was added. The dispersion was transferred to a four-necked flask and replaced with nitrogen at 70 ° C,
The reaction was carried out at a stirring speed of 160 rpm for 5 hours. After this, filtration / washing with water was repeated. The cake-like particles obtained at this time are treated with a hot air drier at 80 ° C. and 85 RH% for 5 hours to agglomerate and melt the particles in a state where the fine particles are present at the interface to block the particles. A substance was obtained. Then, it was air dried at 40 ° C. and 50 RH% for 5 hours. This is a Kryptron System (Kawasaki Heavy Industries; KTM-X
L type) Crushing / surface modification treatment at 18,000 rpm,
Crushed particles having an average particle size of 6 μm were obtained. Further, with respect to 100 parts by weight of the obtained crushed particles, 0.2 part by weight of hydrophobic silica (H-
2000; manufactured by Wacker Co., Ltd.) was treated with an addition Henschel mixer (manufactured by Mitsui Miike Kakoki Co., Ltd.) at 1,500 rpm for 1 minute to obtain a toner A.

Example 2 (Production Example B of toner) Component Styrene 60 n-Butylmethacrylate 35 Methacrylic acid 5 2,2-azobis- (2,4-dimethylvaleronitrile) 0.5 Low molecular weight polypropylene 3 (Viscole 605P; Carbon black 8 (MA # 8; made by Mitsubishi Kasei)

The above materials were mixed with a sand stirrer to prepare a polymerization composition. This polymerization composition was stirred in an aqueous solution of gum arabic having a concentration of 3% with a stirrer TK auto homomixer.
Polymerization reaction was carried out at a temperature of 60 ° C. for 6 hours while stirring at a rotation speed of 4000 RPM using (manufactured by Tokushu Kika Kogyo Co., Ltd.) to obtain spherical particles having an average particle diameter of 6 μm. Separately, tetrafluoroethylene resin dispersion (manufactured by Mitsui DuPont Fluorochemical Co., Ltd.) and hydrophobic titanium oxide (T-805: manufactured by Nippon Aerosil Co., Ltd.) at a solid weight ratio of 5: 1 were sand milled (painted) in an aqueous medium. A conditioner: manufactured by Red Devil Co.) was used to disperse in advance. The tetrafluoroethylene resin / titanium oxide mixture obtained here was added to the above toner dispersion system in an amount of 1.5 parts by weight of solid content based on 100 parts by weight of solid content of the toner, and stirring was continued, and then tetrafluoroethylene resin was formed on the surface of the toner particles. The mixture of titanium oxide and titanium oxide was treated, and filtration / washing with water was repeated. The dispersion was dried and granulated using a drying device (medium flow drying device MSD: manufactured by Nara Machinery Co., Ltd.). As a result, particles were coagulated and melted in a state where fine particles were present at the interface to obtain a block-shaped material. This is a Kryptron system (Kawasaki Heavy Industries Ltd .; KTM-XL type) 1
Crushing / surface modification treatment was performed at 8,000 rpm to obtain crushed particles having an average particle size of 6 μm. Further obtained crushed particles 10
0.2 parts by weight of hydrophobic silica (H-200
0: manufactured by Wacker Co., Ltd. was added, and the resultant was treated with a Henschel mixer (manufactured by Mitsui Miike Kakoki Co., Ltd.) at 1,500 rpm for 1 minute to obtain a toner B.

Comparative Example 1 (Production Example F of Toner) As the composition of the core particles in Example 2, the negative charge control agent chromium complex salt type dye (S-34; manufactured by Orient Chemical Industry Co., Ltd.) 3
Toner F was obtained by the same method except that the weight part was added and the treatment with the resin fine particles and titanium oxide was not performed.

Comparative Example 2 (Toner Production Example G ) 3 parts by weight of the negative charge control agent chromium complex salt type dye (S-34; manufactured by Orient Chemical Industry Co., Ltd.) was added as a core particle composition according to Example 2 and replaced. A toner G was obtained in the same manner as above except that the fine particles of the resin were not added and the treatment with only titanium oxide was performed.

Example 3 (Production Example C of Toner) Production Method of Fine Particles In the same manner as the fine particles a of Example 1, the average particle size of styrene / butyl acrylate = 80/20 was 0.1.
Fine particles c having a glass transition temperature of 70 ° C. and 1 μm were obtained.

Method for producing toner particles 100 g of polyester resin (NE-382; manufactured by Kao Corporation) is dissolved in 400 g of a mixed solvent of methylene chloride / toluene (8/2), and 5 g of phthalocyanine pigment is put into a ball mill and mixed for 3 hours to disperse. To obtain a uniform mixed dispersion liquid. Next, as a dispersion stabilizer, methylcellulose (Methocel K35LV: manufactured by Dow Chemical Co.) 4% solution, 60 g dioctyl sulfosuccinate soda (Nikkor OTP75: Nikko Chemical Co.) 1% solution 5 g, sodium hexametaphosphate (manufactured by Wako Pure Chemical Co., Ltd.) ) In an aqueous solution of 0.5 g dissolved in 1000 g of ion-exchanged water, TK Auto Homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.) was used to adjust the number of revolutions of the above homogeneous dispersion to an average of 3 to 10 μm. It was suspended. The fine particle c dispersion was added and mixed into this suspension at a solid ratio of 5.0 parts by weight with respect to 100 parts by weight of the resin, and the resin fine particles were attached to the surface of the suspended particles. Thereafter, this dispersion was dried and granulated while removing the solvent component by using a drying device (medium flow drying device MSD; manufactured by Nara Machinery Co., Ltd.). As a result, the fine particles were aggregated and melted in a state where they existed at the interface. A block-shaped product was obtained. Kryptron System (Kawasaki Heavy Industries, Ltd .; KT
(M-XL type) is crushed / surface-modified at 16,000 rpm to obtain crushed particles having an average particle size of 6 μm. Three
0.5 parts by weight of hydrophobic titanium oxide (T-805; manufactured by Nippon Aerosil Co., Ltd.) and Ht-2000 (manufactured by Mitsui Miike Kakoki Co., Ltd.) were added at 1,500 rpm. Toner C was obtained by processing for 1 minute.

Example 4 (Toner Production Example D) Method for producing fine particles By the same method as that for the fine particles a in Example 1, styrene / butyl acrylate / 2,2,2-trifluoroethyl acrylate = 70 / Average particle size 0.1 with a composition ratio of 20/10
Uniform particles having a particle size of μm and a glass transition temperature of 70 ° C. were obtained. Further, this dispersion solution was dried using a dispersion coat (manufactured by Nisshin Engineering Co., Ltd.) and powdered to obtain fine particles d.

Method for producing toner particles After wet granulation in Example 2, no tetrafluoroethylene resin dispersion (manufactured by Mitsui DuPont Fluorochemical Co.) was used and only hydrophobic titanium oxide (T-805: manufactured by Nippon Aerosil Co., Ltd.) was used. Was dispersed in advance in a water medium using a sand mill (paint conditioner: manufactured by Red Devil). The mixture of titanium oxide obtained here was added to the above toner dispersion system in an amount of 1.0 part by weight of solid content based on 100 parts by weight of solid content of the toner, and stirring was continued to treat the surface of the toner particles with titanium oxide. After repeating filtration / washing with water, the dispersion was dried and granulated using a drying device (medium flow drying device MSD: Nara Machinery Co., Ltd.). A block-like material was obtained by coagulating and melting. After mixing 100 parts by weight of this block-like material and 8 parts by weight of the above-mentioned fine particles by treating with a Henschel mixer (manufactured by Mitsui Miike Kakoki Co., Ltd.) at 3,000 rpm for 2 minutes, this was mixed with a Kriptron system (Kawasaki Heavy Industries Ltd.). Made;
(KTM-XL type) is crushed / surface-modified at 18,000 rpm to obtain crushed particles having an average particle size of 6 μm, and 100 parts by weight of the crushed particles obtained here is used to prepare hydrophobic silica (0.1 parts). Add 2 parts by weight (H-2000: Wacker Co., Ltd.) and use a Henschel mixer (Mitsui Miike Kakoki Co., Ltd.) at 1,500 rpm.
Toner D was obtained by processing the toner for 1 minute.

Comparative Example 3 (Production Example H of Toner) In place of the resin fine particles d in Example 4, a negative charge control agent chromium complex salt type dye (S-34; manufactured by Orient Chemical Industry Co., Ltd.) 1
Toner H was obtained in the same manner except that parts by weight were used.

Example 5 (Production Example E of Toner) Method for producing fine particles 2,2'-azobis (2-aminodipropane) dihydrochloride
2 g was dissolved in 800 g of ion-exchanged water. The lysate was transferred to a four-necked flask, heated to 70 ° C. after purging with nitrogen,
Add 150 g of methyl methacrylate and stir speed 15
Polymerization was carried out at 0 rpm for 1 hour. After that, 50 g of methyl methacrylate, 4 g of dimethylaminoethyl methacrylate
Was dropped for 1 hour with a dropping funnel. Polymerization was carried out for 4 hours after the completion of dropping, and uniform particles with 0.1 μm and a glass transition temperature of 78 ° C were obtained.
Got

After wet granulation in Example 2, tetrafluoroethylene resin dispersion (manufactured by Mitsui DuPont Fluorochemicals) and hydrophobic titanium oxide (T-805;
Instead of (Japan Aerosil Co., Ltd.), the fine particles e and hydrophobic alumina (Aluminium Oxide C: Japan Aerosil Co., Ltd.) surface-treated with dimethyl silicone) are used in a sand mill in an aqueous medium at a solid weight ratio of 5: 1. It was previously dispersed using a paint conditioner: manufactured by Red Devil. The mixture of the fine particles e / hydrophobic alumina obtained here was added to the above toner dispersion system in an amount of 1.5 parts by weight of solid content based on 100 parts by weight of solid content of the toner, and the stirring was continued and the fine particles e / A mixture of hydrophobic alumina was treated.
After repeating filtration / washing with water, use a hot air dryer to
By treating for 5 hours under the condition of 85 RH%
Agglomerating particles in a state where the fine particles are present at the interface,
In particular, ultrafine particles of 1 μm or less were fixed and fused on the surface of particles of 3 μm or more to obtain a block-like material. 40 ℃, 50
After air-drying at RH% for 5 hours, the Cryptron system (Kawasaki Heavy Industries, Ltd .; KTM-XL type) was crushed / surface-modified at 18,000 rpm to obtain crushed particles having an average particle size of 6 μm. To 100 parts by weight of the crushed particles obtained here, 0.2 parts by weight of hydrophobic silica (R-972: manufactured by Nippon Aerosil Co., Ltd.) was added, and a Henschel mixer (manufactured by Mitsui Miike Kakoki Co., Ltd.) was operated at 1,500 rpm. Toner E was obtained by processing for 1 minute. Further, as the carrier to be mixed with these electrostatic latent image developing toners, three types of carriers A to C3 manufactured as described below were used.

Carrier A polyester resin (Kao; NE-1110) 100 parts by weight, inorganic magnetic powder (TDK; MFP-2) 600 parts by weight, carbon black (Mitsubishi Kasei; MA # 8). Two
Part by weight was thoroughly mixed with a Henschel mixer and pulverized. Next, the mixture was melt-kneaded using an extrusion kneader set to a cylinder portion of 180 ° C and a cylinder head portion of 170 ° C. The kneaded product was cooled and coarsely pulverized, then finely pulverized with a jet mill and further classified with an air classifier to obtain a binder type carrier having an average particle diameter of 55 μm.

Carrier B Ferrite Carrier Core (Powder Tech Co .; F-30
The surface of (0) was coated with a thermosetting silicone resin using a rolling fluid tank (Okada Seiko Co., Ltd .; Spiracoater), and the average particle size was 5
A carrier having a size of 0 μm was used.

Carrier C (1) Preparation of titanium-containing catalyst component In a flask with an internal volume of 500 ml replaced with argon, 200 ml of dehydrated n-heptane was evacuated at room temperature and depressurized at 120 ° C. in advance.
(2mmHg) Dehydrated magnesium stearate 15g (2
(5 mmol) was added to form a slurry. 0.44 g (2.3 mmol) of titanium tetrachloride was added dropwise with stirring, and then the temperature was started and the reaction was carried out under reflux for 1 hour to obtain a viscous transparent titanium-containing catalyst component solution.

(2) Evaluation of activity of titanium-containing catalyst component: 400 ml of dehydrated hexane and 1.8 ml of triethylaluminum were placed in an autoclave having an internal volume of 1 liter which was replaced with argon.
Mmol, diethylaluminum chloride 0.8 mmol, and the titanium-containing catalyst component obtained in the above (1) as a titanium atom, 0.004 mmol was sampled and charged, and
The temperature was raised to 0 ° C. At this time, the system internal pressure was 1.5 kg / cm ² G. Then, hydrogen was supplied and the pressure was increased to 5.5 kg / cm ² G, then ethylene was continuously supplied so that the total pressure was maintained at 9.5 kg / cm ² G, and polymerization was performed for 1 hour to obtain 70 g of polymer. Got The polymerization activity was 365 kg / g · Ti / Hr, and the MFR (melt flowability at 190 ° C. and a load of 2.16 kg; JIS K7210) of the obtained polymer was 40.

(3) Reaction of Titanium-Containing Catalyst Component with Filler and Polymerization of Ethylene 500 ml of dehydrated hexane at room temperature in an autoclave having an internal volume of 1 liter substituted with argon, and sintered ferrite dried under reduced pressure (2 mmHg) at 200 ° C. for 3 hours. Powder F-300 (manufactured by Powder Tech Co., Ltd .; average particle size 50 μm) (450 g) was added, and 0.01 mmol of the titanium-containing polymerization catalyst component of the above (1) was added as a titanium atom, and the reaction was carried out for 1 hour. afterwards,
Ketjen Black EC from the upper nozzle of the autoclave
0.16 g (manufactured by Lion Akzo) was added. As the Ketjen Black EC, one dried under reduced pressure at 200 ° C. and slurried with dehydrated hexane was used. Then, 1.0 mmol of triethylaluminum and 1.0 mmol of diethylaluminum chloride were added, and the temperature was raised to 90 ° C. The system pressure at this time is 1.5k
It was g / cm ² G. The filtrate was raised to supply the hydrogen 2kg / cm ² G, the total pressure is performed continuously fed while 58 minutes polymerize ethylene to keep 6kg / cm ² G, the total amount 472
A polyethylene composition containing g of ferrite and Ketjenblack EC was obtained. It was observed by electron microscopy that the dried powder had a uniform gray color and the ferrite surface was lightly covered with polyethylene. In addition, when this composition was measured by TGA (thermobalance), ferrite: polyethylene: Ketjenblack EC showed 2
The weight ratio was 9: 1: 0.01. Furthermore, the polyethylene-coated ferrite particles obtained here have an opening of 75 μm.
Carrier C was obtained by removing aggregates by sieving and removing free polyethylene particles by sieving with 38 μm openings.

(4) Physical properties of carrier C Average particle size: 51 μm, ferrite filling rate: 96.6 wt%, carrier specific gravity: 4.53, resin layer molecular weight (Mw): 8.1 × 10
¹⁰ and the electrical resistance was 4.5 × 10 ⁹ Ω · cm.

Evaluation of Particle Size of Particles The particle sizes of the toner and carrier were measured as follows. (Toner Particle Size) Toner average particle size was measured using Coulter Counter TA-II type (manufactured by Coulter Counter Co., Ltd.).
It was determined by measuring the relative weight distribution by particle size with a 0 μm aperture tube. (Carrier Particle Size) The carrier particle size was measured using Microtrac Model 7995-10 SRA (manufactured by Nikkiso Co., Ltd.) and the average particle size thereof was determined.

Measurement of Charge Amount and Low Chargeable Toner Amount The charge amount and low chargeable toner amount were measured using the apparatus having the configuration shown in FIG. 1, and the measuring method was performed under the following conditions. 1) Measurement of charge amount The rotation speed of the magnet roll (3) was set to 100 rpm, and the developer used was that after stirring for 30 minutes on the carrier.
1g of this developer is weighed with a precision balance and the conductive sleeve
(2) Place it evenly over the entire surface. Next, the bias voltage from the bias power source (4) is set to 3
KV is applied, the sleeve (2) is rotated for 30 seconds, and the potential Vm when the sleeve (2) is stopped is read. Then the cylindrical electrode
The weight Mi of the separated toner (7) attached to (1) is measured with a precision balance to obtain the average toner charge amount. 2) Measurement of low charge toner amount In the charge amount measurement, the conductive sleeve (2) was applied to the ground without applying a bias voltage, and the same measurement was performed. Electrode (1)
The amount of low-charged toner was determined by measuring whether or not the toner was blown. 3) Measure the above at 25 ° C, 55RH% and 30 ° C, 85
RH% After standing overnight, measurement was performed in that environment.

Image Evaluation Evaluation The toner and the above-mentioned carrier shown in Table 1 were used as toner /
Carriers were mixed at a ratio of 5/95 to prepare a two-component developer. Using this developer, EP-570Z (manufactured by Minolta Camera Co., Ltd.) was used for Examples 1, 2, 4 and Comparative Examples 1 to 3, and for Example 5, EP-408Z.
Various image evaluations shown in Table 1 were performed using (Minolta Camera Co., Ltd.). For Example 3, various evaluations were performed using CF-70 (manufactured by Minolta Camera Co., Ltd.).

(1) Fogging on image As described above, images were printed using the above-mentioned copying machine with various combinations of toner and carrier. Regarding the fogging on the image, the toner fogging on the white background image was evaluated and ranked. It can be practically used in a rank or more, but is preferably in a rank or more.

(2) Printing endurance test Using a chart with a B / W ratio of 6%, a printing endurance test was performed on 10,000 sheets to evaluate images and fog. The results are shown in Table 1. At the same time, the blade cleaning property was evaluated. In the table, ◯ means a practically feasible region, and x means that there is a practical problem. Practical use is possible at a rank of Δ or higher, but ◯ or higher is preferable. In the printing durability test of Example 3, 1000 sheets and 3000 sheets were initially evaluated.

(3) Translucency For Example 3, a translucency test was also conducted. Translucency was evaluated by visually observing the vividness of the color in the projected image when the fixed image on the OHP sheet was projected by the OHP projector. The results are shown in Table 1. O in the table means that the color reproduction is practically usable.

[0067]

[Table 1]

[0068]

The toner of the present invention has improved chargeability and environmental stability, and has little reverse chargeability or low chargeability and less scattering toner. According to the present invention, a small particle size toner can be efficiently manufactured.
The toner of the present invention contains less ultrafine powder. The toner of the present invention has an irregular small particle size and is excellent in blade cleaning property.

[Brief description of drawings]

FIG. 1 shows a schematic configuration of a charge amount and low charge toner amount measuring device according to the present invention.

[Explanation of symbols]

1 Cylindrical electrode 2 Conductive sleeve 3 Magnet roll 4 Bias power supply

Claims (2)

[Claims] 1. A toner produced by granulating particles consisting of at least a resin and a colorant in a wet process, and then aggregating, drying and crushing the particles, wherein charged resin fine particles are fixed on the surface of the toner. Toner. 2. Charged resin fine particles dispersed in a wet method, which is obtained by granulating colored fine particles composed of at least a resin and a colorant in a wet process and then being 1/10 to 1/200 of the average particle size of the colored particles. Toner in a wet state, the chargeable resin fine particles are allowed to exist at the interface of the colored fine particles to be fused and formed into a block, and further crushed.